A good question! the truth is, the fundamental laws which apply to general physic's do not work at the minute sizes worked with at this level.

Relationship of Energy and Matter

According to the older theories of classical physics, energy is treated solely as a continuous phenomenon, whilst matter is assumed to occupy a very specific region of space and moves in a continuous manner.

According to quantum theory, energy is emitted and absorbed in tiny, discrete amounts. An individual bundle or packet of energy, called a quantum, behaves in some situations much like particles of matter; particles are found to exhibit certain wave like properties when in motion and are no longer viewed as localised in a given region but rather as spread out to some degree.

For example, the light (or other radiation) given off or absorbed by an atom has only certain frequencies (or wavelengths), as can be seen from the line spectrum associated with the chemical element represented by that atom. Quantum theory shows that those frequencies correspond to definite energies of the light quanta, or photons, and result from the fact that the electrons of the atom can have only certain allowed energy values, or levels; when an electron changes from one allowed level to another, a quantum of energy is emitted or absorbed whose frequency is directly proportional to the energy difference between the two levels.